20100827

Is reality even stranger than quantum mechanics tells us?

"We know that quantum correlations can be stronger than classical—but why aren't quantum correlations even stronger? Either we are missing something very significant to define quantum theory, or these other theories are all around us too."
– Caslav Brukner (New Scientist)

20100812

Any quantum state can be cloned in the presence of closed timelike curves "The possible existence of closed timelike curves (CTCs) draws attention to fundamental questions about what is physically possible and what is not. An example is the "no cloning theorem" in quantum mechanics — which states that no physical means exists by which an unknown arbitrary quantum state can be reproduced, or copied perfectly. We show here that this theorem can be circumvented in the presence of closed timelike curves, allowing for the cloning of an unknown arbitrary quantum state. Since the "no cloning theorem" has played a central role in the development of quantum information science, it is clear that the existence of CTCs would radically change the rules for quantum information technology." – Tim Ralph, David Ahn, R. B. Mann (arXiv:1008.0221)

20100806

Molecular Simulation with Superconducting Qubits

"Because Nature isn't classical, damnit, and if you want to make a simulation of nature, you'd better make it quantum mechanical. " —Richard Feynman

Georgia, UCSB In arXiv:1008.0701, Pritchett, Martiniset al. introduce a protocol for efficient simulation of molecular dynamics using superconducting qubits. "Recent experimental progress suggests that quantum simulation will be one of the first practical applications of quantum computation. We have shown how quantum computers of only a few qubits can simulate arbitrary quantum systems accurately and quickly, even before they reach the regime of fault tolerant quantum computation."